Many different factors influence safety in traffic situations. For example, vehicle velocity, weather conditions, road conditions and visibility.
A vehicle operator normally continuously monitors the host vehicle surrounding during driving. He/she generally has a good view in a forward direction through the windshield and may thus relatively easy observe the host vehicle surrounding in the forward direction. Hence, he/she can take any observed objects in the forward direction into account when planning an upcoming trajectory for the host vehicle.
The vehicle operator may be able to observe the host vehicle surrounding relatively well in oblique directions forward, except for fields hidden behind A-pillars of the host vehicle. When looking sideways, through side windows of the host vehicle, the vehicle operator can observe the host vehicle surrounding at a left hand and a right hand side of the host vehicle. However, he/she can often only turn his/her head sideways for a short period of time before he/she has to shift focus forward again, wherefore it may be difficult to perceive objects at the left/right hand side of the host vehicle well enough to be able to observe all potential dangers. Further, some fields of his/her view may be hidden behind B-pillars of the host vehicle.
Some rearward directions and sideways directions may be observed via exterior and/or interior rear-view mirrors but some other rearward directions and sideways directions may be difficult or impossible for the vehicle operator to monitor. Such directions or zones are also commonly referred to as blind spots.
Some vehicles are equipped with sensors which aim to aid the vehicle operator in the task of monitoring the vehicle surrounding. Such sensors may also provide information to automatic or autonomous drive systems of the host vehicle. Such systems may provide some semi-automatic, automatic and/or autonomous drive functions and may e.g. assist in lateral and/or longitudinal control of the host vehicle.
The sensors may, at least to some extent, cover some zones which are difficult to monitor for a vehicle operator or a vehicle drive system. However, sensors add costs to vehicles and sensor failure may occur. Further, it may be difficult for a host vehicle operator or a host vehicle drive system to assess if surrounding vehicles are aware of the presence of the host vehicle. Thus, improvements related to safety in traffic situations where more than one vehicle is present are still needed.